Electric type-metal heater for linotype-machines.



D. S. KRAMER. ELECTRIC YPE METAL HEATER FORLINOTYPE MACHINES.

APPLICATION FILED APR.9, 19 12.

3 1 m 0mm is u d em mz m a P ICE D. S. KRAMER. B METAL HEATER FOR LINOTYPE MACHINES. APPLICATION FILED APR.9, 1912.

ELECTRIC TYP Patented Apr. 8, 1913.

2 SHEETSSHEET 2.

fzsi- Svwemtoz Ea flifmmw? DONALD S. KRAMER, 0F COLUMBUS, OHIO.

ELECTRIC TYPE-METAL HEATER FOR LINOTYPE-MACHIN ES.

Specification of Letters Patent.

Patented Apr. 8, 1 913.

Application filed April 9, 1912. Serial No. 689,546.

To all whom it may concern Be it known that I, DofiALn S. KRAMER, a

.citizen of the United States, residing at C0- lumbus, in the county of Franklin, State of Ohio, have invented certain new and useful Improvements in Electric Type-Metal Heaters for Linotype-Machines; and I do hereby declare'the following to be a full, clear, and exact description of the invention, SlfiCll as will enable others skilled in the art to vhich it appertains to make and use the same.

y invention relates tonew and useful improvements in type metal heaters for linotypemachines and more particularly to electrical heaters and the object of my invention is to provide a type metal heater having a primary and secondary winding, the heat being generated by a current induced in the secondary winding by the passage of an alternating current through the primary winding.

A further object of my inventlon is to prothermo actuated cut off for regulating the heat generated. And a still further object of my invention is to improve the construction and increase the efficiency. of devices of the above described character.

With these and other objects in view, my invention will be more fully described, illustrated in the accompanying drawings which show a preferred embodiment of my device and then specifically pointed out in the claims which are attached to and form a part of this application.

In the drawings, Figure 1 is' a central longitudinal section of my type heater. Fig. 2 is a similar section, the inner shell together with the secondary Winding, being shown in elevation. Fig. 3 is a section on the line 33 of Fig. 1. Fig. 4 is a section on the line 44 of Fig. 3.

Referring more specifically to the drawings, in which similar reference numerals esignate corresponding parts throughout, 10 designates in general the body of my heater which, as shown, is largely of the conventional type, comprising a conventional inner shell 11 and an outer shell 12 spaced therefrom. The inner shell is provided. with the customary pump casing 13 having a pump 14 and is cored at one side as vide an automatic,

' at 15 to provide a discharge passage through which a molten metal is forced.

Extending outwardly from the inner shell and insulated therefrom are spaced pins 16 between which are secured the magnetic cores 17 of the secondary winding 18 which winding, is short circuited upon itself and may be formed in one or more sections as desired, each section having one or more turns. The cores of these coils are preferably formed of cast steel or other metal. Positioned above this secondary Winding is an intermediate shell or casing 19, the inner face of which is preferably adapted to reflect the heat generated in the secondary winding against the inner shell of the heater. Surrounding this intermediate casing is the primary winding 20 through which the current passes, said primary winding being opened and closed by means of any suitable form of switch, not shown. An automatic switch or cut off, designated as a whole by the numeral 21 is also electrically connected with the primary Winding in such a manner as to automatically cut off the current through said winding when the temperature of the heater has reached a predetermined point as will be hereinafter explained. As shown, a hot air space is left above the'coils and this-space may be open at the top or not as desired. The secondary winding is preferably provided with a fuse 22 which will blow out if the induced ,current becomes too strong and thus prevent the fusion of a winding. As will be apparent, the passage of an alternating current through the primary winding will induce a current in the secondary Winding, thereby generating heat, the heat generated depending upon the strength of the induced current.-

Referring more specifically to the automatic switch which has been designated as a whole by the numeral 21, said switchwill be seen to consist of a plate of nonconduct-ive material 23 mounted upon the upper edge of the inner shell lland carrying a pair of spaced contacts 24 which are electrically connected with the primary winding in such a-manner that the bridging of these contacts will close the circuit through said winding. Pivoted by one end to this plate is a switch bar 25, which normally bears across the contact pins 24 closingthe circuit. Passing through the plate 23 and.immediately beneath the central portion of the switch bar is a bore which communicates with a bore formed in the inner shell of the heater, said latter bore being designated by the numeral 26 and terminating at its lower end in an enlargement 27 cored in the shell of the heater and forming a chamber or Well which is partially filled .with mercury or other highly expansible fluid. Positioned within the bore 26 is'a float 28 having a stem 29 which extends upwardly through an aperture formed in the switch bar. The intermediate portion of this stem is screw threaded to receive a nut 30 which in normal position bears upon the top of the shell and supports the float. By adjusting this nut the position of the float may be adjusted at will. As will be readily seen the heat of the inner shell will be communicated to the mercury which will expand to come in contact with the float and raise the same until the nut 30engages with the switch bar and raises it, to open the switch. When the switch has been so opened the heating circuit is opened and all further heating of the metal is stopped. As soon as the metal begins to coohthe mercury contracts thereby closing the switch to again heat the metal. By means of this automatic swit h, therefore, it will be apparent that re metal when once melted is maintained a practically constanttemperature that this temperature may be regulated lay the adjustment of the nut 36.

From the "foregoing description it will be apparent that l have provided a simple and etl'ectual electric heater for type metal, similar in all respects to the heater now in use with the exception that the heat is generated electrically.

It will further be seen that l have provided a simple form of thermo actuated, automatic cutoff or switch for maintaining the constant temperature in the heater and for preventing unnecessary consumption of current.

It will of course be understood, that minor changes in the details of construction may be made if desired without in the slightest degree departing from the spirit of my invention.

What I claim is 1. A type metal heater, comprising an inner shell, a secondary windin about said inner shell and insulated there rom, a heat reflecting shell surrounding said winding,

'a primary winding about said reflecting shell, and an outer shell about said primary winding.

2. A type metal heater comprising an inner shell and an outer shell spaced apart, a secondary winding about said inner shell and short circuited upon itself and insulated from such inner shell, a reflecting shell surrounding said secondary winding, a primary winding about said reflecting shell and surrounded by the outer shell, an automatic switch for the primary winding, and a thermo-actuated means for opening and closing said switch.

3. In a device of the character described, the combination with a body portion, including a shell adapted to contain type metal to be heated, said shell having a bore extending longitudinally of the wall thereand a chamber in the wall with which chamber the bore communicates, a primary winding and a secondary winding surroundg the shell, of a switch "for the primary winding including a switch bar pivoted at one end and apertured intermediate its length, a float positioned in said hore a float stem carried by said float ahdextended through the aperture of the switch bar, a nut adjustable upon said stem and below the switch bar, and a thermo expansible liquid in said chamber.

In testimony whereof, I aflix my signature, in presence of two witnesses.

DONALD S. KRAMER.

Witnesses R. H. BARBER, R. O. BRASHARES. 

